<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<script language="javascript" type="text/javascript">
			 function dosomething(damsg, callback){
			 if(typeof callback == "function") callback();
			  console.log(damsg);
			  
			 } 
			dosomething("回调函数", function(){
			  console.log("和 jQuery 的 callbacks 形式一样!");
			});
		</script>
	</body>
</html>
